This microcomputer (PDP 11/03) data system when fully implemented will facilitate the acquisition and processing of information from an analytical ultracentrifuge, a circular dichroic spectropolarimeter, and a laser light scattering instrument used in MDB, NHLBI to investigate the interactions between human lipoprotein subunits. Current capabilities include acquisition, display, and preprocessing of data from the ultracentrifuge and transfer of preprocessed data files to the DECsystem-10 for further analysis. The complex nonlinear analysis necessary for the characterization of interacting systems will be carried out under MLAB on the DECsystem-10. CLINK, the PDP-11/PDP-10 communications software package jointly developed by CSL and CCB, will be used to perform the data transfers. Computation of molecular weights for non-associating systems can be performed in the microcomputer. A commercially available hardware/software package for automating the laser light scattering instrument is being evaluated for possible use with the microcomputer system. Hardware is also being evaluated for performing the analog-to-digital conversion of the signal from the circular dichroic spectropolarimeter.